Air delivery system

ABSTRACT

An air delivery system for particulate material wherein a vacuum is created in an area communicating an intake port with the flow of delivery air and a stream of pressurized air is directed into said area from a point adjacent the intake port to reduce turbulence caused by atmospheric air carrying entrained crop material into said intake port. The system also contemplates gradually expanding the cross-sectional area of the ducts throughout the delivery path to reduce damage to material entrained in the delivery air flow. Both method and apparatus are disclosed.

United States Patent 1 Lundahl 1 May 22, 1973 [54] AIR DELIVERY SYSTEMFOREIGN PATENTS OR APPLICATIONS [7 51 Inventor: Ezra Cordell Lundahl,Idah Fal s, 1,410,260 4/1965 France ..302 5s Idaho 120,446 7/1958U.S.S.R. 302/58 [73] Assignee: Ezra C. Lundahl, Inc., Logan, UtahPrimary Examiner Evon C Blunk [22] Filed: Nov. 4, 1971 AssistantExaminer-H. S. Lane pp No: 195,549 Att0rneyLynn G. Foster [57] ABSTRACT[52] US. Cl. ..302/47, 302/7, 302/66, An air delivery system forparticulate material wherein 56mm" 214/8328 a vacuum is created in anarea communicating an in- [51] It. Cl ..B6Sg 53/40 take p with the flowof delivery air and a stream of [58] Field of Search ..302/58, 56, 47,51, pressurized air is directed into Said ama from a point 302/29 7;214/8328; 56/1316 8 adjacent the intake port to reduce turbulence causedby atmospheric air carrying entrained crop material [56] ReterencesC'ted into said intake port. The system also contemplates UNITED STATESPATENTS gradually expanding the cross-sectional area of the ductsthroughout the delivery path to reduce damage 337,388 3/1886 Fernald etal. ..302/58 to material entrained in the delivery air flow. Both3,556,327 l/l97l Garrison ..302/56 X method and apparatus are disclosed.2,026,291 12/1935 Trimacco ..56/DIG. 8

518,843 4/ 1894 I-Iinkle ..302/7 5 Claims, 3 Drawing Figures PATENTEB WY2 2 I975 SHEET 1 OF 3 FIG. I

PATENTEU H5912 2 I973 SHEET 2 [IF 3 FIG. 2

PATENTED MAY 2 2 I973 SHEET 3 [1F 3 AIR DELIVERY SYSTEM BACKGROUND 1.Field of Invention This invention relates to delivery systems and isparticularly directed to a pneumatic delivery system for particulatecrop material, such as hay or grain.

2. Prior Art Pneumatic or air delivery systems are frequently employedfor delivery of particulate crop material, such as hay or grain, intoand out of wagons, trucks, railroad cars, ships, storage elevators,processing plants and the like. Conventionally, in such systems, a highvelocity flow of air is established through a duct system extendingalong the desired delivery route and the particulate crop material to bedelivered is introduced into the air flow and is carried thereby to thedesired delivery point. Numerous techniques have been employedheretofore for introducing the particulate crop material into the airflow. Some systems have employed mechanical devices for introducing theparticulate crop material into the impellers or fans. However, suchdevices are subject to jamming and wear and require considerablemaintenance. Other systems have employed vacuum techniques for drawingthe particulate crop material into the air flow. However, the airmovement in such systems is generally extremely turbulent with theresult that, where hay is being delivered, the leaves are frequentlytorn from the stems. Thereafter, during ejection of the hay at thedelivery point, the leaves and stems become separated, since the stemsare considerably heavier than the leaves. As a result, the ratio ofleaves to stems varies significantly across the area into which the hayis discharged. Such separation is undesirable since, where the hay isused to feed livestock, the nutritional value of the hay varies with theproportion of leaves. Similarly, where the hay is to be pelletized toproduce feed products, a non-uniform product will result. Where grain isbeing delivered, such turbulence may drive the grain forcibly againstthe duct which tends to crack the hull of the grain and induce spoilage.Moreover, such turbulence provides non-uniform introduction of theparticulate crop material into the air flow and tends to produceclogging of the intake which reduces or blocks the rate at which theparticulate matrial is introduced into the air flow.

It is also customary, in prior art air delivery systems, to graduallydecrease the cross-sectional area of the duct along the length thereofin order to maintain uniform air pressure throughout the deliverysystem. However, the reduction in area increases the likelihood ofcollision between the particulate crop material and the duct and betweenadjacent particles carried by the air flow. These factors tend toincrease the damage to the particulate crop material and stop the freeflow of air in an expanding manner.

BRIEF SUMMARY AND OBJECTS OF THE INVENTION These disadvantages of theprior art are overcome with the present invention and a novel airdelivery system is provided whereby turbulence and damage to theparticulate crop material are significantly reduced while the quantityof particulate material delivered in a given period of time isincreased.

The advantages of the present invention are preferably attained byestablishing a high velocity flow of delivery air through a duct,creating a vacuum adjacent the intake end of the duct, introducingpressurized air adjacent the intake end of the duct upstream from thepoint where the vacuum is created to enhance introduction of particulatecrop material into the flow of delivery air, and gradually expanding thecross-sectional area of the duct along the delivery route to reducedamage to the particulate crop material being delivered.

Accordingly, it is an object of the present invention to provide animproved delivery system for particulate material.

Another object of the present invention is to provide an improvedpneumatic delivery system with the air impellers not coming in contactwith any of the solid crop material entering the air system.

An additional object of the present invention is to provide methods andapparatus for reducing damage to particulate crop material duringdelivery thereof.

A further object of the present invention is to provide improved methodsand apparatus for introducing particulate crop material into an airdelivery system.

Another object of the present invention is to provide methods andapparatus for reducing jamming of the intake of air delivery systems byparticulate crop material presented for delivery.

A specific object of the present invention is to provide methods andapparatus for delivering particulate material comprising establishing ahigh velocity flow of delivery air through a duct, creating a vacuumadjacent the intake end of the duct, introducing pressurized airadjacent the intake end of the duct upstream from the point where thevacuum is created to enhance introduction of particulate crop materialinto the flow of delivery air, and gradually expanding thecross-sectional area of the duct along the delivery route to reducedamage to the particulate crop material being delivered. Thus, alwayshaving the entire air system requiring more air or material to fill thevacuum.

These and other objects and features of the present invention will beapparent from the following detailed description, taken with referenceto the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of a haywagon embodying the air delivery system of the present invention;

FIG. 2 is a diagrammatic representation of the air delivery system ofthe wagon of FIG. 1, with parts broken away for clarity; and

FIG. 3 is the front elevation of an alternative intake mechanism for theair delivery system of FIG. 1.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT In that form of thepresent invention chosen for purposes of illustration in FIGS. 1 and 2,FIG. 1 shows a hay wagon, indicated generally at 2, having a frame 4carried by a suspension system 6 and formed with a suitable hitch 8 forattachment to a tractor or the like, not shown. A receptacle 10 ismounted on the frame 4 to receive hay delivered thereto by a deliverysystem, indicated generally at 12. The suspension system 6 is preferablyof the type shown and described in my copending patent application, Ser.No. 1 17,574, filed Feb. 22, 1971. The details of the receptacle 10 areshown and described in my copending patent applications Ser. No.195,709, filed Nov. 4, 1971, and Ser. No.

195,609, filed Nov. 4, 1971.

The delivery system 12 comprises a rotary rake 14, driven byconventional means, not shown, which picks up hay from the ground anddelivers the hay to the intake port 16 of duct 18 which extendscompletely across the wagon 2. As best seen in FIG. 2, a blower 20supplies a high velocity flow of delivery air into duct 18 throughopening 22 formed in the rear of duct 18 and also delivers a stream ofpressurized air through secondary duct 24 to enter duct 18 adjacentintake port 16. A baffle 26 is mounted internally of duct 18 betweenopening 22 and intake port 16 and serves to produce a Venturi effectwhich creates a vacuum in duct 18 adjacent end 28 of baffle 26. Upperduct 30 has its lower end 32 dimensioned to fit telescopically about theupper end 34 of duct 18. The walls of upper duct 30 diverge outwardlyfrom end 32 so that the crosssectional area of duct 30 graduallyincreases along the length thereof and end 36 of duct 30 is curved todefine a delivery port 38 which cooperates with an opening 40 inreceptacle to deliver hay to the interior of receptacle 10. Obviously,in some instances, it may be necessary or desirable to interpose one ormore intermediate duct sections between the intake duct 18 and thedelivery duct 30. Where this is done, it is preferred that each ductsection be dimensioned to fit telescopically about the next upstreamduct section and that the crosssectional area of each duct section begradually increased throughout the length thereof.

In use, as indicated above, baffle 26 serves to create a vacuum withinduct 18. Air external to duct 18, at atmospheric pressure, tends toenter intake port 16 to fill this vacuum and serves to carry hay,delivered to intake port 16 by rake 14, into duct 18 and to introducethe hay into the flow of delivery air, supplied by blower throughopening 22. In conventional air delivery systems it is found thatconsiderable turbulence is created as the atmospheric air enters duct 18and hay entrained in the turbulent atmospheric air tends to becomeentrapped in the intake port 16 and causes jamming of the intake port16. However, in accordance with the present invention, it is found that,when a stream of pressurized air is introduced into duct 18 adjacentintake port 16 through secondary duct 24, the turbulence is eliminatedor considerably reduced and the hay entrained in the atmospheric air isintroduced smoothly and rapidly into the delivery air, supplied byblower 20 through opening 22. Because of this, the hay feeds into andthrough the delivery system 12 at a higher rate than has been possibleheretofore. Moreover, jamming of the intake port 16 and damage to thehay is significantly reduced. Damage to the hay is further reduced bygradually increasing the cross-sectional area of the delivery system 12along the length thereof. This, of course, reduces the velocity of thedelivery air flow. However, once the hay is entrained in the flow ofdelivery air from blower 20, adjacent end 28 of bafile 26 within duct18, it is found that considerable reduction in the velocity of thedelivery air can be tolerated without releasing the hay. Moreover, thereduction of velocity of the delivery air flow reduces the tendency ofthe delivery air to tear the leaves of the hay from the stems. Moreover,the expansion of the cross-sectional area of the delivery system 12reduces the likelihood of darnage to the hay resulting from collisionsbetween adjacent hay particles or between the hay particles and thewalls of the ducts. Furthermore, even where some tearing of leaves fromstems does occur, the reduction in the velocity of the delivery airtends to minimize separation during discharge of the hay from thedelivery system and, hence, tends to maintain a uniform distrubution ofthe hay quality throughout the receiving receptacle 10.

FIG. 3 illustrates an alternative form of intake for the delivery systemof FIG. 1. In this form, the intake port 42 occupies only a relativelysmall portion of the frontal width of the wagon 2. Hay is picked fromthe ground by belt rake 44 and is delivered to augers 46 which carry thehay to the intake port 42. Intake port 42 is substantially identical infunction to intake port 16 of FIGS. 1 and 2 and pressurized -air issupplied to intake port 42 through secondary duct 48 to enhance feedingof hay through intake port 42 in the same manner as described withrespect to secondary duct 24 of FIGS. 1 and 2.

Obviously, numerous variations and modifications may be made withoutdeparting from the present invention. Accordingly, it should be clearlyunderstood that the forms of the present invention described above andshown in the accompanying drawing are illustrative only and are notintended to limit the scope of the invention.

What Is Claimed Is:

l. A pneumatic crop delivery system comprising: an elongated hollow ductcomprising:

a first horizontally disposed end section having a crop inlet portimmediately above, and adapted to receive said crop on the ground;

a vertically disposed central section;

a second horizontally disposed end section having an elevated cropoutlet port for discharging the crop to a receptacle;

a common source of pressurized air;

means for delivering one portion of the pressurized air to the cropinlet port at the bottom thereof;

means for directing said one air portion generally parallel with andinto said first horizontally disposed end section to carry influent cropto the vertically disposed central section;

means for delivering a second portion of the pressurized air to thelower part of the vertically disposed central section to carry cropreceived from the first horizontally disposed end section up the centralsection, along the second horizontally disposed end section, through thecrop outlet port and into the receptacle.

2. The system of claim 1 further comprising:

said duct being formed with the cross-sectional area of the hollowthereof gradually increasing throughout the length of the duct.

3. The system of claim 1 further comprising:

means for lifting the crop from the ground and delivering the liftedcrop to said inlet port.

4. The system of claim 1 wherein:

said vertically disposed central section of the duct comprises aplurality of hollow components each beingdimensioned to fittelescopically in respect to the adjacent end of the next hollowcomponent to allow extension and contraction of the vertically Idisposed central section through relative displacement of said hollowcomponents without interruption in displacement of crop through theduct.

source vertically into the intermediate portion of the duct where thecrop is being vertically propelled;

carrying said propelled crop upon the additional pressurized air in saidvertical direction to a substantially greater elevation and thereafterdeflecting the propelled crop and pressurized air in a horizontaldirection;

horizontally discharging the crop into a receptacle of the wagon.

1. A pneumatic crop delivery system comprising: an elongated hollow ductcomprising: a first horizontally disposed end section having a cropinlet port immediately above, and adapted to receive said crop on theground; a vertically disposed central section; a second horizontallydisposed end section having an elevated crop outlet port for dischargingthe crop to a receptacle; a common source of pressurized air; means fordelivering one portion of the pressurized air to the crop inlet port atthe bottom thereof; means for directing said one air portion generallyparallel with and into said first horizontally disposed end section tocarry influent crop to the vertically disposed central section; meansfor delivering a second portion of the pressurized air to the lower partof the vertically disposed central section to carry crop received fromthe first horizontally disposed end section up the central section,along the second horizontally disposed end section, through the cropoutlet port and into the receptacle.
 2. The system of claim 1 furthercomprising: said duct being formed with the cross-sectional area of thehollow thereof gradually increasing throughout the length of the duct.3. The system of claim 1 further comprising: means for lifting the cropfrom the ground and delivering the lifted crop to said inlet port. 4.The system of claim 1 wherein: said vertically disposed central sectionof the duct comprises a plurality of hollow components each beingdimensioned to fit telescopically in respect to the adjacent end of thenext hollow component to allow extension and contraction of thevertically disposed central section through relative displacement ofsaid hollow components without interruption in displacement of cropthrough the duct.
 5. A method of conveying crops from the ground into awheeled wagon comprising the steps of: lifting the crop off the groundand directly into a horizontally oriented inlet port of a hollow duct;introducing pressurized air from a common source into the bottom of theduct at the inlet port in a direction generally parallel to thedirection of displacement of the crop through the inlet port; propellingthe crop upon the pressurized air first horizontally ahd thereaftervertically along the hollow of the duct; introducing additionalpressurized air from said source vertically into the intermediateportion of the duct where the crop is being vertically propelled;carrying said propelled crop upon the additional pressurized air in saidvertical direction to a substantially greater elevation and thereafterdeflecting the propelled crop and pressurized air in a horizontaldirection; horizontally discharging the crop into a receptacle of thewagon.